They talked for about an hour of things and persons they remembered in the school.
A. which
B. that
C. who
D. whom
网友回答
A. which
(答案→)B. that
C. who
D. whom
解析：限制行定语从句中，只用that的情况——当先行词既有人又有物，由题可知，先行词为things and persons ，在定语从句中作动词remembered的宾语，本题大意，在大约一个小时的时间里，他们都在谈论学校里记得的那些人和那些事。故B正确。